Dear Yuki:
It means that no voxels were saved as having significant data. The default
significance for SPM is an F threshold of 0.001. It may be that all voxels
were of very low signficance. You can try changing this threshold through
the defaults button and choosing Statistics from the menu. Then set the F
threshold to 1 to save all voxels. It also may mean that you model is
mis-specified and hence there really is nothing significant or that there
is some problem with the realignment of your images. Take a look at
mask.img and make sure it looks like a brain outline (or the outline of
your slices). That way you'll know that at least some voxels were actually
included in the analysis.
Have you tried analyzing this dataset in spm99? Did that give you results?
If so then you may have specified the spm2b analysis incorrectly.
Darren
At 04:19 AM 12/27/2002 +0000, you wrote:
>Hello, SPM experts,
>I am trying out the spm2b right now. But, I got stuck with
>the following error message. This was at the "Estimate" step,
>after done with pre-processing . I did the [fMRI stats model setup]
>for both [design] and [data], and got the spm.mat.
>
>I am not sure what's going wrong here.
>Please.. any suggestion will be greatly appreciated!
>
>
>============================================================================
>Plane 69/69 , block 35/40 : ...read & mask data
>Plane 69/69 , block 36/40 : ...read & mask data
>Plane 69/69 , block 37/40 : ...read & mask data
>Plane 69/69 , block 38/40 : ...read & mask data
>Plane 69/69 , block 39/40 : ...read & mask data
>Plane 69/69 , block 40/40 : ...done
>Warning: No inmask voxels - empty analysis!
> > In c:\spm2b\spm_spm.m at line 723
>Warning: Divide by zero.
> > In c:\spm2b\spm_spm.m at line 739
>Warning: Divide by zero.
> > In c:\spm2b\spm_spm.m at line 740
>Temporal non-sphericity (over voxels) : ...REML estimation
>Warning: Divide by zero.
> > In c:\spm2b\spm_spm.m at line 751
> ReML Block - 1
>??? Index exceeds matrix dimensions.
>
>Error in ==> c:\spm2b\spm_spm.m
>On line 783 ==> [Vp,hp] = spm_reml(Cy(q,q),Xp,Qp);
>
>??? Error while evaluating uicontrol Callback.
>
>===========================================
>
>Thanks a lot in advance,
>Yuki Chen
-------------------------------------------------------------------------
Darren R. Gitelman, M.D.
Cognitive Neurology and Alzheimer¹s Disease Center
E-mail: [log in to unmask]
WWW: http://www.brain.northwestern.edu
Voice: (312) 908-9023
Fax: (312) 908-8789
Northwestern Univ., 320 E. Superior St., Searle 11-470, Chicago, IL 60611
-------------------------------------------------------------------------
|